37 research outputs found
The Hercules pseudoscorpions from Madagascar: A systematic study of Feaellidae (Pseudoscorpiones: Feaelloidea) highlights regional endemism and diversity in one of the āhottestā biodiversity hotspots
Madagascar is amongst the āhottestā biodiversity hotspots with extreme levels of diversity and endemism. Throughout the last decades, there has been substantial progress in documenting the Malagasy invertebrate fauna but no study has ever focused on pseudoscorpions (Arachnida: Pseudoscorpiones) in the arachnid fauna. Here we review the Malagasy fauna of Hercules pseudoscorpions (family Feaellidae), which are common in soil habitats of arid biomes across Madagascar. Using morphology and molecular data, we recover three reciprocally monophyletic clades that correspond to three new genera in well-defined biogeographical regions and identify twelve new species: Antsiarananaella gen. nov. for Antsirananaella lorenzorum sp. nov., Antsiarananaella leniae sp. nov., Antsiarananaella faulstichi sp. nov. and Antsiarananaella marlae sp. nov.; Mahajanganella gen. nov. for Mahajanganella fridakahloae sp. nov., Mahajanganella heraclis sp. nov. and Mahajanganella schwarzeneggeri sp. nov.; Toliaranella gen. nov. for Toliaranella fisheri sp. nov., Toliaranella griswoldi sp. nov., Toliaranella mahnerti sp. nov., Toliaranella meridionalis sp. nov. and Toliaranella pumila sp. nov. Local endemism in this fauna is high and most species have small distributions, ranging from 20 km to 350 km linearly. Genetic distances between populations are also high, suggesting restricted dispersal or selection against dispersal in this fauna. Speciesā ranges seem to be delimited by geological barriers including volcanic fields (Ambre-Bobaomby in the north of Madagascar), mountain ranges (foothills of the Central Highland Plateau), and rivers (Manankolana, Mandrare, Manombo and Onilahy Rivers and their anabranches), but mainly by different biome habitats. Overall, Madagascar emerges as a global āhotspotā of feaellid radiation and these animals may be used in future studies to test biogeographical hypotheses across xeric biomes on this island
Global disparities in surgeonsā workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study
: The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSSĀ® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 Ā± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 Ā± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 Ā± 4.9 and 7.8 Ā± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 Ā± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity > 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI
Molecular phylogeography of the troglobiotic millipede Tetracion Hoffman, 1956 (Diplopoda, Callipodida, Abacionidae)
More than 85 species of cave-obligate (troglobiotic) millipede have been described from North America. Understanding the patterns and processes that determine their distribution in this region is an area of recent research. Here, we present the first molecular phylogeographic study of troglobiotic millipedes. Millipedes of the genus Tetracion Hoffman, 1956 (Callipodida: Abacionidae) inhabit caves on the Cumberland Plateau in Tennessee and Alabama, a global hotspot for cave biodiversity. Three species have been described: T. jonesi Hoffman, 1956, T. antraeum Hoffman, 1956, and T. tennesseensis Causey, 1959. To examine genetic divergence within and between species of Tetracion we sequenced part of the mitochondrial cytochrome oxidase 1 gene from 53 individuals from eleven caves across the range of T. tennesseensis and in the northern part of the range of T. jonesi. We found: (1) little variation within species (six haplotypes in T. tennesseensis and four haplotypes in T. jonesi, with a maximum of 1.4% intraspecific divergence between haplotypes), (2) that gene flow between caves is limited (7 of 10 haplotypes were restricted to a single cave, and FST > 0.80 and P < 0.05 for fifteen of eighteen comparisons between caves), and (3) significant genetic divergence between species (8.8% between T. tennesseensis and T. jonesi). Our results are consistent with previous morphology-based species definitions showing T. tennesseensis and T. jonesi belonging to distinct taxa. Our research contributes to the growing body of phylogeographic information about cave species on the Cumberland Plateau, and provides a point of comparison for future studies of troglobionts and millipedes
Integrative revision of the giant pill-millipede genus Sphaeromimus from Madagascar, with theĀ description of seven new species (Diplopoda, Sphaerotheriida,Ā Arthrosphaeridae)
The Malagasy giant pill-millipede genus Sphaeromimus de Saussure & Zehntner, 1902 is revised. Seven new species, S. titanus sp. n., S. vatovavy sp. n., S. lavasoa sp. n., S. andohahela sp. n., S. ivohibe sp. n., S. saintelucei sp. n., and S. andrahomana sp. n. were discovered, in one case with the help of sequence data, in the rainforests of southeastern Madagascar. The species are described using light- and scanning electron microscopy. A key to all 10 species of the genus is presented. All but one (S. andohahela) of the newly discovered species are microendemics each occurring in isolated forest fragments. The mitochondrial COI barcoding gene was amplified and sequenced for 18 Sphaeromimus specimens, and a dataset containing COI sequences of 28 specimens representing all Sphaeromimus species (except S. vatovavy) was analyzed. All species are genetically monophyletic. Interspecific uncorrected genetic distances were moderate (4ā10%) to high (18ā25%), whereas intraspecific variation is low (0āĀ3.5%). Sequence data allowed the correct identification of three colour morphs of S. musicus, as well as the identity of a cave specimen, which although aberrant in its morphology and colouration, was genetically identical to the holotype of S. andrahoma
Homology of the Lateral Eyes of Scorpiones: A Six-Ocellus Model
<div><p>Scorpions possess two types of visual organs, the median and lateral eyes. Both eyes consist of simple ocelli with biconvex lenses that differ in structure and function. There is little variation in the number of median ocelli across the order. Except for a few troglomorphic species in which the median ocelli are absent, all scorpions possess a single pair. In contrast, the number of pairs of lateral ocelli varies from zero to five across Scorpiones and may vary within species. No attempt has been made to homologize lateral ocelli across the order, and their utility in scorpion systematics has been questioned, due to the variation in number. A recent study examined the number of lateral ocelli among various Asian Buthidae C.L. Koch, 1837 and proposed a āfive-eye modelā for the family. This model has not been examined more broadly within Buthidae, however, nor compared with the patterns of variation observed among other scorpion families. An eyespot, referred to as an accessory lateral eye, situated ventral or posteroventral to the lateral ocelli, has also been reported in some scorpions. Analysis of its structure suggests it serves a nonvisual function. We present the first comparative study of variation in the lateral ocelli across the order Scorpiones, based on examination of a broad range of exemplar species, representing all families, 160 genera (78%), 196 species (9%), and up to 12 individuals per species. We propose a six-ocellus model for Recent scorpions with four accessory ocelli observed in various taxa, homologize the individual ocelli, and correct erroneous counts in the recent literature. We also investigate the presence of the eyespot across scorpions and discover that it is more widespread than previously recognized. Future work should investigate the genetic and developmental mechanisms underlying the formation of the lateral ocelli to test the hypotheses proposed here.</p></div
Lateral ocellus counts in Recent scorpion families, according to the literature.
<p>Lateral ocellus counts in Recent scorpion families, according to the literature.</p
Lateral ocelli of Recent scorpions (families Diplocentridae Karsch, 1880; Hemiscorpiidae Pocock, 1893; Heteroscorpionidae Kraepelin, 1905; Hormuridae Laurie, 1896; Scorpionidae Latreille, 1802; Urodacidae Pocock, 1893).
<p><i>Hemiscorpius lepturus</i> Peters, 1861, ā (AMNH [LP 11080]), Type 3A. <b>B.</b><i>Heteroscorpion magnus</i> LourenƧo & Goodman, 2002, paratype ā (FMNH), Type 2B. <b>C.</b><i>Urodacus manicatus</i> (Thorell, 1876), ā (AMNH), Type 2B. <b>D.</b><i>Cheloctonus jonesii</i> Pocock, 1892, ā (AMNH), abnormal four-ocellus condition with PLMi (Type 4B) on dextral side. <b>E.</b><i>Cheloctonus jonesii</i> Pocock, 1892, ā (AMNH), Type 3A. <b>F.</b><i>Hormiops davidovi</i> Fage, 1933, ā (AMNH), Type 2B. <b>G.</b><i>Diplocentrus rectimanus</i> Karsch, 1880, ā (AMNH [LP 2032]), abnormal four-ocellus condition with APLMi<sub>2</sub> on dextral side. <b>H.</b><i>Nebo hierichonticus</i> (Simon, 1872), ā (AMNH), Type 3A. <b>I.</b><i>Liocheles australasiae</i> (Fabricius, 1775), ā (AMNH), Type 3A. <b>J.</b><i>Tarsoporosus macuira</i> Teruel & Roncallo, 2010, ā (AMNH), Type 4B. <b>K.</b><i>Oiclus purvesii</i> (Becker, 1880), ā (AMNH [LP 9037]), Type 2B. <b>L.</b><i>Pandinus gregoryi</i> (Pocock, 1896), juv. ā (AMNH), Type 3A. <b>M.</b><i>Opistophthalmus jenseni</i> (Lamoral, 1972), ā (AMNH), abnormal seven-ocellus condition with MLMa, PLMa, PLMi, PDMi, APLMi<sub>1</sub>, APLMi<sub>2</sub> and APLMi<sub>3</sub>. <b>N, O.</b><i>O. jenseni</i>, ā (AMNH [AH 4039]), abnormal five-ocellus condition with MLMa, PLMa, PDMi, PLMi and APLMi<sub>2</sub> on sinistral side (<b>N</b>) and MLMa, PLMa, PDMi, PLMi and ADMi on dextral side (<b>O</b>). <b>P.</b><i>Opistophthalmus</i> sp., ā (AMNH), Type 4B. <b>Q.</b><i>Scorpio maurus palmatus</i> (Ehrenberg, 1828), ā (AMNH), Type 4B. <b>R.</b><i>Scorpio maurus palmatus</i> (Ehrenberg, 1828), ā (AMNH), Type 3A. Abbreviations: anterodorsal minor ocellus (ADMi); APLMi<sub>1</sub>, APLMi<sub>2</sub>, APLMi<sub>3</sub> (accessory posterolateral minor ocelli); MLMa (mediolateral major ocellus); PDMi (posterodorsal minor ocellus); PLMa (posterolateral major ocellus); PLMi (posterolateral minor ocellus). Scale bars ā=ā0.1 mm.</p
Number of genera, species and individuals examined for study of lateral ocelli in Recent scorpion families.
<p>Number of genera, species and individuals examined for study of lateral ocelli in Recent scorpion families.</p
Recent scorpion families and genera in which an eyespot is present, including observations from the literature [27]ā[30].
<p>Recent scorpion families and genera in which an eyespot is present, including observations from the literature <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0112913#pone.0112913-Spreitzer1" target="_blank">[27]</a>ā<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0112913#pone.0112913-Tikader1" target="_blank">[30]</a>.</p
Lateral ocelli of Recent scorpions (families Chactidae Pocock, 1893; Chaerilidae, Pocock, 1893; Euscorpiidae, Laurie, 1896; Iuridae Thorell, 1876; Pseudochactidae Gromov, 1998; Scorpiopidae Kraepelin, 1905).
<p><b>A.</b><i>Chaerilus variegatus</i> Simon, 1877, ā (AMNH), abnormal three-ocellus condition with PLMi. <b>B.</b><i>C. variegatus</i>, ā (AMNH [LP 6390]), abnormal three-ocellus condition with ALMa. <b>C.</b><i>C. variegatus</i>, ā (AMNH [LP 6389]), Type 2A. <b>D, E.</b><i>Chaerilus chapmani</i> Vachon & LourenƧo, 1985, ā (AMNH), Type 2A on sinistral side (D), abnormal one-ocellus condition without MLMa (Type 1) on dextral side (E). <b>F.</b><i>Pseudochactas ovchinnikovi</i> Gromov, 1998, subad. ā (AMNH), Type 1. <b>G.</b><i>Troglocormus ciego</i> Francke, 1981, holotype ā (AMNH), Type 4C. <b>H.</b><i>Protoiurus kraepelini</i> (von Ubisch, 1922), ā (AMNH), Type 4C. <b>I.</b><i>Calchas birulai</i> Fet et al., 2009, ā (AMNH), Type 4C. <b>J.</b><i>Megacormus gertschi</i> DĆaz Najera, 1966, juv. ā (AMNH [LP 6474]), Type 4C. <b>K.</b><i>Euscorpius italicus</i> (Herbst, 1800), ā (AMNH [LP 10297]), Type 3B. <b>L.</b><i>Troglocormus willis</i> Francke, 1981, ā (AMNH), Type 3B. <b>M.</b><i>Chactopsis insignis</i> Kraepelin, 1912, ā (AMNH [LP 8420]), Type 4C. <b>N.</b><i>Parascorpiops montana</i> Banks, 1928, lectotype ā (MCZ), Type 3A. <b>O.</b><i>P. montana</i>, paralectotype ā (MCZ), Type 2A. <b>P.</b><i>Alloscorpiops</i> sp., ā (AMNH [LP 11279]), Type 4B. <b>Q.</b><i>Scorpiops feti</i> KovaÅĆk, 2000, ā (MCZ), Type 4B. <b>R.</b><i>Euscorpiops kaftani</i> (KovaÅĆk, 1993), juv. ā (AMNH [LP 11371]), Type 4B. Abbreviations: ADMi (anterodorsal minor ocellus); ALMa (anterolateral major ocellus); e (eyespot); MLMa (mediolateral major ocellus); PDMi (posterodorsal minor ocellus); PLMa (posterolateral major ocellus); PLMi (posterolateral minor ocellus). Scale bars ā=ā0.1 mm.</p